Ariana's response to Pete's message about bullying read: "I know u already know this but I feel I need to remind my fans to please be gentler with others," she wrote. "I really don’t endorse anything but forgiveness and positivity. I care deeply about Pete and his health. I’m asking you to please be gentler with others, even on the internet."

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Pete's message touched on BPD (borderline personality disorder), which he was diagnosed with last year. He's always been open and honest about his disorder and, a while back, he wrote on Instagram about the misconceptions of dating when you have BPD.

“Just because someone has a mental illness does not mean they can’t be happy and in a relationship. It also doesn’t mean that person makes the relationship toxic.

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“I just think it’s fucked up to stigmatise people as crazy and say that they are unable to do stuff that anyone can do. It’s not their fault and it’s the wrong way for people to look at things.”